ec1fea4516
A previous commit enabled the tracking of object allocations in Linux-backed caches from the SPL layer for debuggability. The commit is: 9a170fc6fe54f1e852b6c39630fe5ef2bbd97c16 Unfortunately, it also introduced minor performance regressions that were highlighted by the ZFS perf test-suite. Within Delphix we found that the regression would be from -1%, all the way up to -8% for some workloads. This commit brings performance back up to par by creating a separate counter for those caches and making it a percpu in order to avoid lock-contention. The initial performance testing was done by myself, and the final round was conducted by @tonynguien who was also the one that discovered the regression and highlighted the culprit. Reviewed-by: Matt Ahrens <matt@delphix.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com> Closes #10397
35 lines
857 B
Plaintext
35 lines
857 B
Plaintext
dnl #
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dnl # 3.18 API change,
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dnl # The function percpu_counter_init now must be passed a GFP mask.
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dnl #
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AC_DEFUN([ZFS_AC_KERNEL_SRC_PERCPU_COUNTER_INIT], [
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ZFS_LINUX_TEST_SRC([percpu_counter_init_with_gfp], [
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#include <linux/gfp.h>
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#include <linux/percpu_counter.h>
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],[
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struct percpu_counter counter;
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int error;
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error = percpu_counter_init(&counter, 0, GFP_KERNEL);
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])
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])
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AC_DEFUN([ZFS_AC_KERNEL_PERCPU_COUNTER_INIT], [
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AC_MSG_CHECKING([whether percpu_counter_init() wants gfp_t])
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ZFS_LINUX_TEST_RESULT([percpu_counter_init_with_gfp], [
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AC_MSG_RESULT(yes)
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AC_DEFINE(HAVE_PERCPU_COUNTER_INIT_WITH_GFP, 1,
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[percpu_counter_init() wants gfp_t])
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],[
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AC_MSG_RESULT(no)
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])
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])
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AC_DEFUN([ZFS_AC_KERNEL_SRC_PERCPU], [
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ZFS_AC_KERNEL_SRC_PERCPU_COUNTER_INIT
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])
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AC_DEFUN([ZFS_AC_KERNEL_PERCPU], [
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ZFS_AC_KERNEL_PERCPU_COUNTER_INIT
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])
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